U.S. Pat. No. 4,498,351 to R. Ahoor is drawn to a hydraulically and continuously regulated mechanical advantage chain drive mechanism. Equally displaced sectors for receiving the chain are provided using equally pressured cylinders and pistons to achieve equal displacement of the sectors.
U.S. Pat. No. 3,087,349 to G. B. Herting is drawn to a hydraulically adjustable peripheral portion of a pulley wheel to gain continuous adjustment with the need of using different-sized pulleys.
U.S. Pat. No. 3,613,468 to S. Rand is drawn to a continuously variable transmission system employing a segmented pulley mounted on parallel conic axial members hydraulically controlled.
U.S. Pat. No. 724,449 to W. N. Dumaresq is drawn to a mechanically adjustable continuously variable chain transmission using spur gears.
U.S. Pat. No. 3,850,044 to D. H. Hagen is drawn to a mechanically adjustable continuously variable chain transmission using spur gears for a bicycle.
U.S. Pat. No. 3,969,948 to C. D. Pipenhagen, Jr. is drawn to a continuously variable bicycle automatic transmission that the mechanical advantage is regulated by external resistance to pedaling of a bicycle using spur gears.
U.S. Pat. No. 3,995,508 to H. R. Newell is drawn to a continuously variable bicycle automatic transmission that the mechanical advantage is regulated mechanically using spur gears with a dampener to reduce cyclic fluctuations in the drive ratio.
None of the above noted patents are seen to disclose the specific arrangement of concepts disclosed by the present invention.